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arXiv · 2512.21772

Time-dependent fluctuating local field approach for description of the correlated fermions dynamics

L. D. Silakov·Ya. S. Lyakhova·A. N. Rubtsov
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Abstract

We formulate a time-dependent Fluctuating Local Field (TD-FLF) method for correlated fermion dynamics, extending the stationary FLF approach. The wavefunction is approximated as an ensemble of non-interacting states subject to a classical fluctuating field, with dynamics encoded in the field's time-dependent distribution. This reduces the time-dependent Schr\"odinger equation to a generalized eigenvalue problem in a significantly reduced basis. Applied to half-filled 2D Hubbard lattices, TD-FLF yields highly accurate results, outperforming mean-field theory and capturing oscillation frequencies and amplitudes in good agreement with exact diagonalization. Its low computational cost and flexibility make TD-FLF a promising tool for simulating driven correlated systems.

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L. D. Silakov, Ya. S. Lyakhova, A. N. Rubtsov. 2025-12-25. Time-dependent fluctuating local field approach for description of the correlated fermions dynamics. https://arxiv.org/abs/2512.21772

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